A conventional card-type smart key may be implemented in a thin and flat form relative to a fob-type smart key so that it is easy for a user to carry.
FIGS. 1 and 2 are views illustrating a conventional card-type smart key.
A conventional card-type smart key 10 may include a mechanical key 3, a battery 5, and a printed circuit board (PCB) 7 which are inside a housing 1 of a card type. The card-type smart key 10 may accommodate the mechanical key 3 and the battery 5 inside the housing 1 of the card type. However, generally, this card-type smart key does not include key buttons because a security problem may occur due to incorrect operation in implementing a remote key entry (RKE) function for remotely controlling a door by applying the buttons.
Therefore, the conventional card-type smart key implements only a passive access function for controlling a door of a vehicle only by buttons of the vehicle after a user approaches the vehicle.
Hereinafter, the passive access function will be described.
If the conventional card-type smart key 10 is located within a preset distance from a vehicle 20, the card-type smart key 10 may receive a low frequency (LF) signal from an external antenna. The LF signal may be an LF signal corresponding to at least one of a door lock button, a door unlock button, and a trunk or tail gate open button of the vehicle 20.
Upon receiving the LF signal, the smart key 10 may generate a radio frequency (RF) signal corresponding to the received LF signal. The vehicle 20 may receive the RF signal generated by the conventional card-type smart key 10 may perform a function corresponding to the LF signal.
For example, when a door open button attached to a door handle of the vehicle 20 operates, the conventional card-type smart key 10 may receive an LF signal corresponding to a door open function from the vehicle 20 and output a door open signal corresponding to the LF signal to the vehicle 20 as an RF signal.